From: Christophe Leroy christophe.leroy@csgroup.eu
(backported from upstream 8a5299a1278eadf1e08a598a5345c376206f171e)
For different reasons, fsl-spi driver performs bits_per_word modifications for different reasons: - On CPU mode, to minimise amount of interrupts - On CPM/QE mode to work around controller byte order
For CPU mode that's done in fsl_spi_prepare_message() while for CPM mode that's done in fsl_spi_setup_transfer().
Reunify all of it in fsl_spi_prepare_message(), and catch impossible cases early through master's bits_per_word_mask instead of returning EINVAL later.
Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Link: https://lore.kernel.org/r/0ce96fe96e8b07cba0613e4097cfd94d09b8919a.168037180... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/spi/spi-fsl-spi.c | 50 +++++++++++++++++++++------------------------- 1 file changed, 23 insertions(+), 27 deletions(-)
--- a/drivers/spi/spi-fsl-spi.c +++ b/drivers/spi/spi-fsl-spi.c @@ -201,26 +201,6 @@ static int mspi_apply_cpu_mode_quirks(st return bits_per_word; }
-static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs, - struct spi_device *spi, - int bits_per_word) -{ - /* CPM/QE uses Little Endian for words > 8 - * so transform 16 and 32 bits words into 8 bits - * Unfortnatly that doesn't work for LSB so - * reject these for now */ - /* Note: 32 bits word, LSB works iff - * tfcr/rfcr is set to CPMFCR_GBL */ - if (spi->mode & SPI_LSB_FIRST && - bits_per_word > 8) - return -EINVAL; - if (bits_per_word <= 8) - return bits_per_word; - if (bits_per_word == 16 || bits_per_word == 32) - return 8; /* pretend its 8 bits */ - return -EINVAL; -} - static int fsl_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) { @@ -248,9 +228,6 @@ static int fsl_spi_setup_transfer(struct bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi, mpc8xxx_spi, bits_per_word); - else - bits_per_word = mspi_apply_qe_mode_quirks(cs, spi, - bits_per_word);
if (bits_per_word < 0) return bits_per_word; @@ -368,14 +345,27 @@ static int fsl_spi_do_one_msg(struct spi * In CPU mode, optimize large byte transfers to use larger * bits_per_word values to reduce number of interrupts taken. */ - if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) { - list_for_each_entry(t, &m->transfers, transfer_list) { + list_for_each_entry(t, &m->transfers, transfer_list) { + if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) { if (t->len < 256 || t->bits_per_word != 8) continue; if ((t->len & 3) == 0) t->bits_per_word = 32; else if ((t->len & 1) == 0) t->bits_per_word = 16; + } else { + /* + * CPM/QE uses Little Endian for words > 8 + * so transform 16 and 32 bits words into 8 bits + * Unfortnatly that doesn't work for LSB so + * reject these for now + * Note: 32 bits word, LSB works iff + * tfcr/rfcr is set to CPMFCR_GBL + */ + if (m->spi->mode & SPI_LSB_FIRST && t->bits_per_word > 8) + return -EINVAL; + if (t->bits_per_word == 16 || t->bits_per_word == 32) + t->bits_per_word = 8; /* pretend its 8 bits */ } }
@@ -658,8 +648,14 @@ static struct spi_master * fsl_spi_probe if (mpc8xxx_spi->type == TYPE_GRLIB) fsl_spi_grlib_probe(dev);
- master->bits_per_word_mask = - (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) & + if (mpc8xxx_spi->flags & SPI_CPM_MODE) + master->bits_per_word_mask = + (SPI_BPW_RANGE_MASK(4, 8) | SPI_BPW_MASK(16) | SPI_BPW_MASK(32)); + else + master->bits_per_word_mask = + (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)); + + master->bits_per_word_mask &= SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)